Spark Plugs

Inspect the spark plug tip for wear and damage. If the tip is covered with carbon, replace the plug. Do not drop or shock the spark plug. If the ceramic body is broken, replace the plug.

Removal & Installation

Before servicing the vehicle, refer to the Precautions Section.

NOTE

Disconnecting the negative battery cable on some vehicles may interfere with the functions of the on-board computer systems and may require the computer to undergo a relearning process, once the negative battery cable is reconnected.

NOTE

If working near and/or around the SRS system and components, be sure to properly disable the SRS system. See disarming/arming the SRS system.

Disconnect the negative battery cable.

Remove the necessary components to gain access to the spark plugs.

Disconnect the spark plug wires from the spark plugs. Be sure to mark the wires for reinstallation.

Remove the spark plug from its mounting.

Fig. Spark plug wire routing (1 of 2)-1991-1993

Fig. Spark plug wire routing (2 of 2)-1991-1993

To install:

NOTE

Be sure to use new fasteners, as required.

NOTE

Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread sealer are identified. Do not use paints, lubricants or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners.

Installation is the reverse of the removal procedure.

Using the GM diagnostic scan tool or aftermarket equivalent reprogram the necessary systems and components. Be sure to follow the scan tool manufacturer-s directions.